Patients with multiple sclerosis present with focal lesions throughout the spinal cord. There is a clinical need for non-invasive measurements of spinal cord activity and functional organization in multiple sclerosis, given the cord's critical role in the disease. Recent reports of spontaneous blood oxygenation level-dependent fluctuations in the spinal cord using functional MRI suggest that, like the brain, cord activity at rest is organized into distinct, synchronized functional networks among grey matter regions, likely related to motor and sensory systems...

Elevated relative cerebral blood volume on perfusion MRI and increased uptake on C-methionine PET can be used to diagnose and guide biopsy of brain tumors but are not specific. We report increased uptake on C-methionine PET associated with 4 developmental venous anomalies (DVAs) in 3 children with brain tumors, which could potentially mimic tumor and misdirect biopsy. Because DVAs are not readily visible on CT, prevention of misdirected biopsy in patients with focally elevated C-methionine uptake and relative cerebral blood volume relies on close correlation with contrast-enhanced anatomic MRI to exclude DVA or other nonneoplastic etiology...

OBJECTIVE: Arterial spin-labelling (ASL) MRI uses intrinsic blood water to quantify the cerebral blood flow (CBF), removing the need for the injection of a gadolinium-based contrast agent used for conventional perfusion imaging such as dynamic susceptibility contrast (DSC). Owing to the non-invasive nature of the technique, ASL is an attractive option for use in paediatric patients. This work compared DSC and multi-timepoint ASL measures of CBF in paediatric brain tumours. METHODS: Patients (n = 23; 20 low-grade tumours and 3 high-grade tumours) had DSC and multi-timepoint ASL with and without vascular crushers (VC)...

BACKGROUND: For children with sickle cell anaemia and high transcranial doppler (TCD) flow velocities, regular blood transfusions can effectively prevent primary stroke, but must be continued indefinitely. The efficacy of hydroxycarbamide (hydroxyurea) in this setting is unknown; we performed the TWiTCH trial to compare hydroxyurea with standard transfusions. METHODS: TWiTCH was a multicentre, phase 3, randomised, open-label, non-inferiority trial done at 26 paediatric hospitals and health centres in the USA and Canada...

A multifunctional microRNA, miR-155, has been recently recognized as an important modulator of numerous biological processes. In our previous in vitro studies, miR-155 was identified as a potential regulator of the endothelial morphogenesis. The present study demonstrates that in vivo inhibition of miR-155 supports cerebral vasculature after experimental stroke. Intravenous injections of a specific miR-155 inhibitor were initiated at 48 h after mouse distal middle cerebral artery occlusion (dMCAO). Microvasculature in peri-infarct area, infarct size, and animal functional recovery were assessed at 1, 2, and 3 weeks after dMCAO...

OBJECTIVE: The purpose of this study was to develop and test a clinically relevant method to mechanically stimulate lumbar functional spinal units while recording brain activity by means of functional magnetic resonance imaging (MRI). METHODS: Subjects were investigated in the prone position with their face lying on a modified stabilization pillow. To minimize head motion, the pillow was fixed to the MRI headrest, and supporting straps were attached around the shoulders...

Improvised explosive devices (IEDs) are one of the main causes for casualties among civilians and military personnel in the present war against terror. Mild traumatic brain injury from IEDs induces various degrees of cognitive, emotional and behavioral disturbances but knowledge of the exact brain pathophysiology following exposure to blast is poorly understood. The study was aimed at establishing a murine model for a mild BI-TBI that isolates low-level blast pressure effects to the brain without systemic injuries...

The ability of trypanosomes to invade the brain and induce an inflammatory reaction is well-recognized. This study uses magnetic resonance imaging (MRI) in conjunction with a murine model of central nervous system (CNS) stage trypanosomiasis to investigate this phenomenon at the level of the blood-brain barrier (BBB). Mice were scanned before and after administration of the contrast agent. Signal enhancement maps were generated, and the percentage signal change was calculated. The severity of the neuroinflammation was also assessed...

OBJECTIVE: Poststroke hyperglycemia is common and is associated with increased risk of death and dependence, but appropriate management remains uncertain. Glucose potassium insulin (GKI) infusion did not benefit patients with moderate poststroke hyperglycemia in a recent trial. Using magnetic resonance imaging (MRI), previous studies identified a relationship between recruitment of ischemic tissue to the final infarct and hyperglycemia, possibly mediated by brain lactic acidosis. METHODS: We undertook a randomized, placebo-controlled trial of GKI infusion in patients with blood glucose >126mg/dl (7mmol/l) within 24 hours of ischemic stroke...

Distributions of current produced by transcranial direct current stimulation (tDCS) in humans were predicted by a finite-element model representing several individual and collective refinements over prior efforts. A model of the entire human head and brain was made using a finely meshed (1.1x1.1x1.4mm(3) voxel) tissue dataset derived from the MRI data set of a normal human brain. The conductivities of ten tissues were simulated (bone, scalp, blood, CSF, muscle, white matter, gray matter, sclera, fat, and cartilage)...

Cerebral ischaemia usually results in the rapid death of neurons within the immediate territory of the affected artery. Neuronal loss is accompanied by a sequence of events, including brain oedema, blood-brain barrier (BBB) breakdown, and neuroinflammation, all of which contribute to further neuronal death. Although the role of macrophages and mononuclear phagocytes in the expansion of ischaemic injury has been widely studied, the relative contribution of these cells, either of exogenous or intrinsic central nervous system (CNS) origin is still not entirely clear...

Hepatic encephalopathy (HE) is normally diagnosed by neuropsychological (NP) tests, which are not very specific and do not reveal the underlying pathology. Magnetic resonance imaging (MRI) and spectroscopy (MRS) of the brain offer alternative and possibly more specific markers for HE. These methods were applied in conjunction with NP testing in order to determine their usefulness in the identification of HE and to understand the pathogenesis of HE more clearly. MR imaging and spectroscopy examinations, in addition to a battery of 15 NP tests, were administered to investigate 31 patients awaiting liver transplantation and 23 healthy controls...